SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0109b543f16aabdda0f23c47365df4b5e3969350c4e9d3557a60682ffa9590e' 
  AND token = 'JzteQK9QK2C/Iyuxj8UGz83+kx0+h5I8mMi3i2OiV3Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}