SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c252813abaecd2f1af2163f9effc097de625fed50b7fb8f35a724835137a0e02' 
  AND token = 'Pa91yCCNfa8Kzww+SCzVU2nDRpe83pWcAP2L0A8wmCM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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