SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbe0a017e95f8727ab7622164586096c16b5303614b0f4c069e06706d0c5ee8e' 
  AND token = 'tUwJCI9iahXtdD/wii0cQYzceZ31oaZScLIIAligSCs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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