SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd69e7260eb40a2a62d14b152131543a0db7a73c9c5a00cf3c04fd0fe93d036a' 
  AND token = 'sPWepIMhn3gGLM5/Xf6kdbQvnNW+M6xcTs3w8YIvQAw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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