SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d34d746400867ac86d893bef0c5ac52e40905288750f58307dbd1f0f7063242' 
  AND token = 'jihiVn+NKOBX76NF4JYHAhBaOcrpKi1uLbfhP2rBdq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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