SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7bce3879813eb89b554b6abe86e0f9c7a8618af28402bfe46a942828d0b2df0b' 
  AND token = 't6m69mAxYsPjTWd82YNdA1BXR9VDwN/RWbenD4E75gs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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