SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '00b83bcc6933de67f4409aa76db02c55786c4441ebbdaa1117b95abdb59569f4' 
  AND token = 'SSrJLxg6AmSzB4GbB3Sb3qNjoplt94EWaWq34Mp+4Ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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