SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e22e6e98256ec82ae1b44c99fcd994d76c80e45c4a8707bf81c3e9dcd3c3b410' 
  AND token = 'uk25WEdPMUousrFQvhQM4i+ULZn8JXAGeVQeAjLmUvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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