SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f155fb5a8ba3f2f590fc4f0e09b229dd963716ff3c04bfce36b13cef1cc99fb1' 
  AND token = 'e2pd2I4p48R8f6phBMwiXnHSsURYw9lZHpqIRxSmmZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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