SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61d120d4d547df745b524fd869b941edf95ace872829b8e240927a135d1c6019' 
  AND token = 'hsQfnNrE1KkFm2bewCGaznLUZDGv3wYpf+9frhD6iEw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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