SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23117eca2a92fb664e273e30a065087e2556d8fd41c1bcecd36ea0cdbe41044f' 
  AND token = 'kXNt4Ro/0Sop+qN4ssabewXYH+DjeUgWLfvHN3mpeyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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