SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89f0978d51cd93d857a31ade097d44ea4017f03c3a3127ac1253ec91a34b6ec5' 
  AND token = 'cgtFciA4K1IPDtVAr/f0X+wZAfPYGytppIQGnhR0mqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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