SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32cb9ea9b67195bb37c5411e017a9ef620836f616b773ce9d4313027b91c487f' 
  AND token = 'wtbMD2DTZg8UNFceGZp6pr+NSXLshrLUlvCrlEaLH4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}