SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bec2c97a40690a914816f55f6273f0400c13f480622bbc891e9d0c1da8f3a73' 
  AND token = 'Ajfad1+wrhPsZGXowb/uP8eUnsJxvzas4OYL1uFP/2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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