SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a04e950f22183108c2fa5711647f684b0399875185db201812ecb2552385dbcf' 
  AND token = '2wrQZzFLWIhRNLqS4MkVuqSRZsHhF3YjqpUmoGnpgLY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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