SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '609ccf98f7099a4a4b7ed688e4062c7feda298ad0ed05c3209b7634998fe88b8' 
  AND token = 'bge4ftPhzeLo6HOwusmDJpIAwNJn9iH1fpwHCjU4NFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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