SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd80918a7332b98bb231bb38f8cb204a26514f0fcc09c23b5b19f978ed4c79f1' 
  AND token = 'OPiygf9zSHoDWRjS1woEZRHwJEyk53WJfhA3ET/diU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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