SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dee9094c1818b2aec29e22c339a6b37a67dd0f74d5fd8118845211dde47d0f5b' 
  AND token = '1CqzcLwSphTxKP255hHNcRxS9elDTbrIA4ESVCqZrV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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