SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2f00a06c366f38997d9c78c41add4be33965ebd12095c6e804127c5fa288f94' 
  AND token = 'GpqqzwVPXRjgvMN1fhcnUjhUjXgN2HJCtt+CcqewcKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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