SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87830e7a718b8a551f5735880939f89630ed61e154db38f91eb3cdd00c02854a' 
  AND token = 'DU2EzHLdXLmNX2vSuZropYFMYDfG8atlCvz+6QZkSmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00256

JSON explain

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