SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4934294d4e6392b9982d3e79774c06a44266a59fbe60fc2ab3edd47c6ae60023' 
  AND token = 'Gi5Sdy7CzeAiS2kAqDRWZ0FATmlridtqPXlRy+dXd4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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