SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5658e4e059fdb4432ffd57aba03e18d350c9c2acfe9c019977e86f7143820429' 
  AND token = 'QTfbEnglO6A/dUqBNJ1kGmw+2/sgRJF8+933eDOzocY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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