SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bdada674021bf6d571cd058df56764191e769d43b1814413feedddc85f3faf76' 
  AND token = 'pX8Z0qJsy9e6AS/wmY2/2lHYDjguCAtt2gbC6hqXTV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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