SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab0d2a0933731b3c96b40a881945b1cb05dbf0c74052089791f34689e557601b' 
  AND token = 'Cnp3MQvPXVKO1x4fKGK249/5ZGuz/wzWwL1ACqMMd4c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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