SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9125077b2a991084a56cfede79402d3cfb4547a02d1db830f2c05b57caf0ffc3' 
  AND token = 'R+ZlwjWTq5CQ3jWFhqy3T/TZpCulwUJXgZbAs/StIVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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