SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63181be614102bb386ecbe4d64b103b7b0947e6502342bab4e891ec218818640' 
  AND token = 'dKlU4sZEDSM9ovT2Ei2mCD9RTcXnkWGuaY6COwykpV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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