SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e0298c95a846d71f345cffe4d1d8c4b92ed377e1d6a05d8f309c60f57bf8609' 
  AND token = 'rFYAG/9dvINHEhDgUcSCYhqJUJAtaDjnX2+oTh67NaE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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