SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9818552d371186828c1b9b7ae6a26656451b8b8f9ddc809fab9241b211d08fe1' 
  AND token = 'wB8nYycpU66V/SBrACUNpHMj9bLxBz9h11/fjDNEk94=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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