SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acd088efb96e38f776174c595f8f81fc29ad1191721c569a932df58034d5efc6' 
  AND token = '0gIUSWOPBfNq3IMKb1I6ykEgnXiKsMrVwe3h3K15Pa4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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