SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aae2a619e55dfffbe49a094bf5c1ce6c210c521cb18733b44755836bd487544a' 
  AND token = 'AGxiAhu+6KT0CO7V5sxh/r/lylzjPilwAhuUM/R3mWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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