SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cbe06134212931a5c6fe7484ec38ffc89decbe4deec9c65b7ecd9e4c48b2d67' 
  AND token = 'C0Qr7CBKmjC8QKbXW2QwxjHnX7XRHbLMdmXZ8K49cbg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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